According to the Motion Picture Association of America (“MPAA”), the piracy of motion pictures has grown to the point where it has cost the Industry (and the U.S. economy), in hard goods alone (e.g. DVDs) approximately $3.4 billion in 2003, up from $2.2 billion in 1998. According to a report by Solomon Smith Barney, the cost of piracy reached $5.4 billion in 2005. The MPAA further states that 90% of that loss, in the critical first 6-8 weeks of a given title's release, is due to unauthorized camcording of movies in theaters with subsequent duplication and illicit sales in DVD form. Additional losses occur elsewhere (e.g. on the internet and via VHS videocassettes).
In an address delivered to the Society of Motion Picture and Television Engineers (“SMPTE”) on May 17, 2005, an executive in change of anti-piracy efforts for a major motion picture studio stated that “good pirate DVD copies are available on the black market within 14 days of a movie's release.” Sometimes, in fact, pirate DVDs duplicated from masters camcorded at advance screenings appear on the street, or on the internet, before the movie actually opens.
The problem is so severe that the MPAA members have even openly discussed the possibility of releasing movies to the DVD market and to theaters on the same “day-and-date,” which would obliterate the usual “window” of theatrical primacy. If that were to happen, many experts say that the theatrical exhibition industry would suffer massive losses and might be forced to close as many as 50% of the theaters in the United States alone. The economic losses due to all of this could thereby vastly exceed the losses suffered by the MPAA members, as well as drastically altering the nature of cinema itself.
Much of this illegal duplication, distribution and smuggling of stolen intellectual property is perpetrated by internationally based organized crime gangs that are, concurrently, also engaged in drug trafficking. It has been said that, pirates actually make more money from illicit DVDs than they do from heroin, with far less risk of punishment, if any. In places like Russia, Indonesia, Malaysia and China, experts suggest that more than 90% of the DVDs purchased by consumers arise from pirated content.
In conjunction with the MPAA, film laboratories now use forensic “watermarking” technology to identify specific film prints that are distributed to theaters, a practice that allows law enforcement to trace pirated movies to the theaters from which they were stolen. But by the time the movies are traced, the piracy has already occurred and the damage is done. Watermarking does little more than provide law enforcement a clue to the scene of the initial crime. Pirates are mobile and can capture movies at a variety of sites all over North American and beyond. Accordingly, a long felt need exists to hinder, if not inhibit, the ability of pirates to capture movies in theaters.
When considering the technological challenges of video cameras shooting images projected by film and digital projectors in theaters, it is necessary to consider the differences between film and digital projection in theaters and the basics of video capture of the sort used by pirates.
Film cameras and projectors typically photograph and display images at the rate of 24 still photos per second, each one of which is captured by the camera in about 1/50th of a second. But, typically, film projectors then display those images by showing each image or “frame” twice. In other words, the film going public sees a series of 24 separate images every second in 48 flashes of light interrupted by moments of darkness during which the film projector's shutter cuts off all light on the screen. The rotating shutter of a film camera is typically set at 180° so as to provide an approximate 50th of a second exposure every 1/24 of a second; a 50% duty cycle. But theatrical film or digital projectors show these images differently. Whereas with film cameras, a 180° exposure is followed by 180° of shuttered darkness, in the projector, those moments of darkness are bisected into two 90° intervals that are placed equidistantly apart from one another. Thus, a normal projection sequence for one frame would be:                 1/96 sec. of dark, 1/96 sec. of light, 1/96 sec. of dark, 1/96 sec. of light=total time 1/24 second.        
Or, stated in decimal equivalents:                0.0104 sec. dark, 0.0104 sec. light, 0.0104 sec. dark, 0.0104 sec. light=total time 0.041 second.        
The duty cycle of a film camera looks like a circle bisected into 180° segments, with each segment signifying: (1) exposure; and (2) composition, and viewing while the next increment of film is pulled into position and registered in the camera gate. The duty cycle of a film projector looks like a circle bisected by two wedges on opposing sides—a bowtie—representing the pulldown interval of 12 ms, and a like interval mirrored at 180° that represents the display interval and the shutter cycle.
The moments of darkness that occur during shuttering are not seen by the public because of a phenomenon called persistence of vision, first observed by Aristotle in ancient times. Persistence of vision is the tendency of the “eye” to see images for a few moments after the retina senses them. Thus, people are usually unaware of the blinking of their own eyes.
The reason for the double-display of each image that comprises “motion pictures” is that shuttering of those 24 images at a rate of 24 flashes of light and dark would result in a noticeable flicker to the majority of viewers. A higher flicker rate, 48 flashes of light and dark, however, appear as a constant flow of images to the majority of viewers because the flash rate is faster than their persistence of vision.
This so-called “critical flicker frequency” occurs as a result of one's persistence of vision. The critical flicker frequency can best be explained as the phenomenon that occurs when rotating a cylinder, half of which is painted black, the other half of which is painted white. As the cylinder is rotated, one first sees black, then white, and so forth. But as the rotational speed increases, one's persistence of vision eventually causes the incoming images to fuse together and the eye begins to see grey. The critical flicker frequency is the frequency in which the black and white sides of the rotating cylinder appears grey to the eye. Critical flicker frequency, also sometimes referred to as “flicker fusion threshold,” can also be defined as the transition point of an intermittent light source where the flickering light ceases and appears as a continuous light. There are a multitude of factors that determine our perception of flicker that includes the intensity and size of the test stimulus. Likewise, in movies, at the critical flicker frequency of 48 flashes per second, one sees a continuous flow of images, each one merging into the next.
Some theatrical projectors have a three-bladed shutter that generates a flash rate of 72 flashes-per-second (three flashes of light for every film image). Three-bladed shutters are sometimes used in smaller screening rooms to reduce light levels on an overly bright screen, but it is also used to eliminate all vestiges of flicker. Sometimes, on very large screens with very bright scenes, image flicker that occurs with a double-bladed shutter can be eliminated with a three-bladed shutter. Some major motion picture studios have screening rooms that employ three-bladed shutters because of this, but they are rarely used in commercial settings because they require higher light levels to yield the same brightness on screen, which is more costly for theatrical exhibitors because of the high cost of xenon bulbs and the additional electricity required to power them.
Three-bladed shutters were common in the days of silent movies, where the more-or-less standard 16 frames-per-second capture rate was insufficient to reach the threshold of the critical flicker frequency. So by using a three-bladed shutter, 16×3=48 flashes-per-second, the critical frequency was attained. When sound was introduced in 1929-1930, it was necessary to increase the frame rate to 24 in order to enable the recording of intelligible analog sound on film. At that point, it became possible to make use of a double-bladed shutter and still reach the critical flicker frequency of 48 flashes-per-second.
The 72 flash-per-second model that one would see when using a three-bladed shutter with standard 24 frames-per-second motion pictures would rise to 144 flashes-per-second if used with the non-standard frame rate of 48 frames-per-second, currently under consideration by some filmmakers and others in the motion picture industry.
In all these instances, the display rate of the individual film images and the film projector's flash rate on screen are at variance with the various standards for video capture. Also, it is important to consider the fact that most video cameras “integrate” an image (equivalent to the exposure interval in film cameras) in about 33 ms, given optimal brightness. If a video camera is confronted by less than optimal brightness, greater “gain” is provided to the CCD or other capture means so as to increase sensitivity, but such additional gain also generates a higher degree of video “noise,” which is more-or-less equivalent to the greater “grain” evident in “faster” film stocks. Conversely, when a higher than optimal amount of light is present, video cameras bring it down so as to fall within their useful dynamic range by employing an electronic shuttering means. The electronic shutter method adjusts the 33 ms integration period to something less than 33 ms to adjust for this increased light level.
Some video cameras, such as those manufactured by Canon, have a new shutter speed control called “clear scan.” This option is designed to adjust the camera shutter speed based on alternate scan frequencies, such as those presented by televisions or computer monitors. The clear scan shutter speed has a range from 60.5 Hz to 201.5 Hz with 120 steps in between. However, once this speed is set it operates in a symmetrical manner and would require a return to a set-up menu to make further adjustments.
Therefore, even if the pirate is using a Canon camera equipped with “clear scan” adjustments, opportunities exist with the present invention to use combinations of altered display intervals, phase shifted with non-standard shutter intervals. Also, in accordance with the invention, altered patterns, cadences and/or shapes may be used to confound the ability of camcorders to capture film and digitally projected images on screen.
Digital projectors are now making an appearance in a few theaters. But they do so without using light-blocking shuttering as is common with film projectors. Such shuttering is unnecessary because there is no need for new media (film) to be pulled into position in front of an aperture, an operation that must be hidden by shuttering. Rather, such devices project a near constant stream of ever changing images that correspond to standard frame rates for film, video and/or any non-standard frame rate. For that reason, pirates who are camcording movies projected by such digital systems get an even better image than when they steal film projections.
U.S. video cameras typically capture video at the rate of 29.97 frames-per-second (usually, and erroneously, said to be 30 frames-per-second), which generates an NTSC standard with an interlaced image that has, in total, 525 lines of resolution per frame, in 60 fields (each video frame is composed of two fields). Not coincidentally, the 60 frame-per-second architecture of U.S. television matches the 60 Hz frequency of North American electrical power, whereas the 50 Hz basis of European power coincides with their 25 frame-per-second video frame rate, which is composed of 50 fields.
The discrepancy of the frame rates between film and video creates a problem if one tries to photograph an ordinary television with a film camera running at the standard 24 frames-per-second. The resulting film shows black bars rolling through the film's depiction of the television picture, as if the television set's horizontal hold control was failing. This is the result of the film camera's under-sampling a higher frame rate, which results in revealing the TV blanking interval. In order to capture a television image on film, it is necessary to synchronize both film camera and video display to 24-frame video on the television (specially converted for this specific purpose, using specialized video equipment) or use a specific, non-standard shutter angle in the film camera. Movie pirates are doing the reverse of that when they photograph 24-frame film with video cameras that operate at either “30” frames-per-second, 25 frames-per-second, or in some cameras at the so-called 24 frames-per-second “progressive” (non interlaced) mode, or at 30 frames-per-second progressive, 60 frames-per-second progressive.
Because of frame rate discrepancies, the process of transferring film to video is a tricky business that involves precise timing between the film's movement and the video capture systems used by major postproduction facilities. Professional telecine systems, such as those from Cintel (illustrated in FIG. 1) or Philips, accomplish the task in a very precise manner, for example, using a “3:2 pulldown” scheme illustrated in FIG. 2. But as tricky as it is to transfer 24 frame-per-second film to 30-frame video on a professional level, and as costly and sophisticated as telecine systems are, it is remarkable how well the job can be done with small, cheap, readily available consumer level camcorders.
The bulk of piracy is accomplished with such consumer cameras, particularly those that record onto mini-DV tape (as shown in FIG. 3), which is easily converted to DVD for duplication. Some newer camcorders can even record directly to DVDs (such as the cameras shown in FIG. 4 and FIG. 5), directly onto internal hard-drives, on onto removable “flash memory” devices, which could further facilitate the ability of thieves to quickly duplicate and sell stolen movies.
Pirates gain entry to theaters with their cameras hidden in bags and/or purses or, commonly, under coats that evade scrutiny of theater staff. Professional cameras, being significantly larger and heavier, are more difficult to hide. So consumer cameras, from both low-end single chip models through high-end 3-chip models and various high definition formats can be assumed to be the means of capture by most pirates. In the U.S. most such cameras capture images in accordance with the NTSC “30” video frames (actually 29.97) composed of 60 video fields (one video frame equals two fields). There are also many digital cameras and capture devices that can operate in various modes, including both interlaced and progressive scan; cameras designed to operate at 24p (24 frames-per-second progressive scan, really 23.98 frames-per-second), 30p (30-frame progressive); and PAL camcorders that operate at 25 frames-per-second (interlaced), are also used, with further resolution choices that include standard 525 NTSC, but also 1080i, 480p, and 720p and 1080p. There are also cameras that have variable frame rates from as high as about 5,000 frames-per-second down to almost zero.
Interlacing means that each video frame is composed of two fields of information wherein the odd lines are traced first, followed by a moment's “blanking.” Even lines are traced thereafter, or vice versa. Some video cameras are also capable of operating without interlacing and capture images in one fell swoop, with “progressive” scanning at 24 images-per-second (referred to as “24p”). In this manner both even and odd lines are traced in one “progressive” pass. In Europe, of course, camcorders are available that operate at the PAL standard of 25 frames-per-second, or with SECAM standards. Anti-piracy experts say that PAL camcorders produce pirate masters that are superior to those made with NTSC.
But however the digital video master is acquired, regardless of the format used by the camcorder, such digital video masters are the beginning of the chain of criminal theft of intellectual property that then stretches around the world and down onto the streets of cities everywhere. Efforts to quell duplication, distribution and sales of illicit copies of movies all take place after the fact of the initial theft from theaters, and that is where the present invention seeks to stop this costly shoplifting.